25. A woman runs a marathon in 30°C weather and replaces all volume lost in sweat by drinking dis...
25. A woman runs a marathon in 30°C weather and replaces all volume lost in sweat by drinking distilled water. After th A) decreased total body water (TBW) B) decreased haematocrit C) decreased intracellular fluid (ICF) volume e marathon, she will have decreased plasma osmolarity increased intracellular osmolarity 26. Which of the following ions has a higher concentration in intracellular fluid (ICF) than in extracellular fluid (ECF)? C1 D) HC03 E) Ca2+ 27. One gram of mannitol was injected into a woman. After equilibration, a plasma sample had a mannitol concentration of 0.08 g/L During the equilibration period, 20% of the injected mannitol was excreted in the urine. The subject's A) extracellular fluid (ECF) volume is 1 L B) intracellular fluid (ICF) volume is 1 L C) ECF volume is 10 L D) ICF volume is 10 L interstitial volume is 12.5 28. 、 Excitability, in neurophysiology, is defined as: A) presence of a resting membrane potential B) use of more than 30% ofATP synthesizedforp powering the Na-K ATPase response to a threshold stimulus with a propagated action potential presence of voltage gated ion channels in a tissue 29. An excitable cell has an RMP of-70 mV and a firing level of - 50 mV. This cell would be inexcitable when its membrane potential is: A) -30 mV B) -55 mV 70mV 30. Though the equilibrium potential of Na is + 60 mV, membrane potential does not reach this value during the overshoot of the action potential because D) -90mV the concentration gradient of Na is reversed Na channels undergo inactivation in 1 ms C) voltage gated K channels open when t membrane potential reaches 0 mV the membrane is impermeable to Na
25. A woman runs a marathon in 30°C weather and replaces all volume lost in sweat by drinking distilled water. After th A) decreased total body water (TBW) B) decreased haematocrit C) decreased intracellular fluid (ICF) volume e marathon, she will have decreased plasma osmolarity increased intracellular osmolarity 26. Which of the following ions has a higher concentration in intracellular fluid (ICF) than in extracellular fluid (ECF)? C1 D) HC03 E) Ca2+ 27. One gram of mannitol was injected into a woman. After equilibration, a plasma sample had a mannitol concentration of 0.08 g/L During the equilibration period, 20% of the injected mannitol was excreted in the urine. The subject's A) extracellular fluid (ECF) volume is 1 L B) intracellular fluid (ICF) volume is 1 L C) ECF volume is 10 L D) ICF volume is 10 L interstitial volume is 12.5 28. 、 Excitability, in neurophysiology, is defined as: A) presence of a resting membrane potential B) use of more than 30% ofATP synthesizedforp powering the Na-K ATPase response to a threshold stimulus with a propagated action potential presence of voltage gated ion channels in a tissue 29. An excitable cell has an RMP of-70 mV and a firing level of - 50 mV. This cell would be inexcitable when its membrane potential is: A) -30 mV B) -55 mV 70mV 30. Though the equilibrium potential of Na is + 60 mV, membrane potential does not reach this value during the overshoot of the action potential because D) -90mV the concentration gradient of Na is reversed Na channels undergo inactivation in 1 ms C) voltage gated K channels open when t membrane potential reaches 0 mV the membrane is impermeable to Na